This invention relates to shock absorbing equipment, and more particularly to protective shock absorbing athletic equipment for wear during contact sports, and to methods for making such equipment.
Shock absorbing equipment has long been known and used where shock attenuation is required. For example, to reduce the trauma inflicted upon people in vehicle collisions, closed-cell foam materials have been used in automobile dash boards, sand-filled barrels have been deployed about highway obstructions, and air-bags that inflate upon vehicle impact have been used in passenger compartments. Raw cotton and wool batting have been used for padding and packaging needs, and both batting and inflatable members have been used in clothing and athletic equipment.
Athletic equipment, such as shoulder pads, rib protectors, hip pads, thigh pads, and so forth, are commonly worn by participants in a great variety of sports in which body contact with either another participant or with a piece of equipment used in the sport presents the risk of injury. Such equipment has long been known and used by athletes in contact sports such as football, hockey and so forth.
One type of known prior art athletic equipment includes a relatively hard outer shell of leather, vulcanized fiber, or similar material, and an inner layer of soft padding material. So constructed, the hard outer layer receives the applied force or shock and serves to spread the force over a large area where it is absorbed and cushioned by the soft padding material. Known prior art padding materials include cotton padding, foam rubber, foam plastic material, sponge rubber, expanded rubber or vinyl and the like, with the resilience of such material tending to absorb a portion of the applied force.
Another known type of athletic equipment includes an inflatable balloon-like structure which is inflated with air to a pressure above one atmosphere and then sealed to maintain the air within the structure. When a force is imparted to such a structure, a portion of the air volume within the structure immediately adjacent the point of contact on the structure is forced to another region within the structure causing the entire structure to balloon. This ballooning effect tends to redistribute the applied force in the same manner that stepping on one end of an elongated balloon redistributes the applied force to the other end of the balloon causing the other end to bulge.
The known prior art shock absorbing equipment, however, does not effectively reduce the force actually imparted to the user to a negligible value.